R&D activity of SAGBO avoidance for the CS insert fabrication

The fabrication of the center solenoid (CS) insert is under way in the engineering design activity (EDA) of International Thermonuclear Experimental Reactor (ITER), the purpose of the CS insert is to measure the performance of Nb/sub 3/Sn conductor for ITER, the R&D activities of the strain accelerated grain boundary oxidation (SAGBO) avoidance was carried out for the CS insert fabrication. The shot peening and the flow control were established for the heat treatment of Nb/sub 3/Sn processing. The effect of the chromium plating on the Nb/sub 3/Sn strands was clarified by the several specimens.